Clinical Research Studies

40 subjects with a confirmed diagnosis of IBD or >6 months post-RYGB with a diagnosed USD event or kidney stone on imaging within the past three years and 40 healthy subjects will be administered a high oxalate diet on Days 0-3 and Days 21-24 with a washout period on Days 4-7 and will be administered 250mg sodium oxalate on Days 8-20, via prepared spinach, from Weil Cornell Medicine’s Clinical and Translational Science Center. Subjects will partake in four stool collections, four 24-h urine collections, two blood collections, and four sets of colonic permeability testing. Subjects are placed on prepared-controlled diets obtained from the metabolic kitchen at Weill Cornell Medicine’s Clinical and Translation Science Center with moderately high oxalate (MOx) during Days 0-3 and Days 21-24. Diets will contain 16% protein, 30% fat, and 54% carbohydrate, and are controlled in the amounts of calcium (400mg), oxalate (250mg), ascorbic acid (50mg), fiber (30 grams) and other nutrients. The MOx diet will be compared against healthy controls with no chronic diseases, not on any chronic medications, no history of GI pathology, or urinary stone disease (USD).